RUPTURE OF THE FLEXOR METATARSI. 
707 
difficult. Judging by the many reported cases, union is almost always 
complete in four to eight weeks, even when both legs are affected, though 
one case in a riding-horse lasted for three months. In rare instances 
. recovery does not occur, or is so incomplete as to impair the movement 
of the hock. These depend on the position of the rupture and on the 
animal not being rested sufficiently long. Where the tendon is divided 
in the mucous bursa, or torn away from its point of origin on the femur 
(a rare occurrence), recovery is less assured, because formation of new 
tissue remains incomplete, the paratendineum essential to union being 
absent from the tendon sheath and mucous bursa. On account of the 
Fig. 261.—Rupture of flexor metatarsi muscle (from a photograph). 
peculiar nature of its insertion into the femur, the tendon rarely tears 
away, but when this occurs a fresh difficulty arises, because the new 
tissue consists of callus, which must grow both from the torn end of the 
tendon and from the femur. It is somewhat doubtful whether in 
Goubaux’s case the tendinous or the muscular portion of the flexor 
metatarsi was torn away ; the point is of little importance. Probably it 
was the tendinous portion, because muscle is very rarely torn away from 
its insertion into bone. H. Bouley reports similar cases. As a rule even 
when the tendon is torn away from its insertion the case finally recovers, 
though it lasts as many months as the other weeks, and slaughter is 
often preferable to treatment. 
Partial recovery is one of the results of putting the horse to work 
z z 2 
